intranasal delivery comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Last reviewed on 2026-01-22. Where a claim depends on a specific study, the study is described rather than over-claimed.
Published studies examine a fairly narrow set of endpoints. Rodent experiments commonly measure maze learning, infarct volume after induced ischemia, and tissue levels of neurotrophic factors. Clinical reports from Russian centres describe attention, memory and recovery scores in patients after stroke or transient ischemic attack. Most of those human studies are small and few have been repeated by independent groups. Outcome measures differ between studies, which limits direct comparison.
Circulation time for the peptide is short because peptidases cleave it readily. The Pro-Gly-Pro tail is thought to slow breakdown compared with the bare ACTH fragment, but the gain appears modest. Absorption after intranasal dosing is limited, and only a fraction of a dose is expected to reach the central nervous system. Laboratory concentrations therefore sit well above levels achieved systemically, a gap that complicates translation from bench findings to clinical claims.
The mechanisms attributed to semax are inferred from animal and cell studies rather than traced to one confirmed target. The most frequently cited pathway involves increased expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal and cortical tissue. Some work points to engagement of melanocortin receptors, particularly MC4, which the parent ACTH fragment can activate. Effects on dopaminergic and serotonergic signalling have also been reported. No single account explains all observed results, and the relative weight of each pathway remains unsettled.
Lyophilised powder is normally kept at -20 °C in a desiccated container, with some suppliers recommending -80 °C for long-term archival storage. Repeated freeze-thaw cycles are the most common cause of avoidable loss, so aliquoting before freezing reduces variability between working sessions. Dissolved peptide is far less stable than the dry solid and is usually prepared fresh or held briefly at 4 °C. Aqueous solutions support both hydrolysis of the backbone and oxidation of the N-terminal methionine, and these two routes dominate degradation under ordinary laboratory conditions.
Identity and purity are confirmed with reversed-phase high-performance liquid chromatography, typically monitored at 214 nanometres where the peptide bond absorbs. Mass spectrometry, either electrospray or MALDI-TOF, verifies molecular mass against the theoretical value and detects truncation or adduct formation. Amino acid analysis and peptide mapping provide additional confirmation when required. The most frequently reported impurities are deletion sequences from incomplete coupling, methionine sulfoxide from oxidation, and dimeric species formed through non-covalent aggregation. Impurity profiles depend strongly on the synthesis and purification route chosen by the producer.
Published research has focused mainly on neurological and cognitive endpoints in animal models, with proposed mechanisms involving brain-derived neurotrophic factor and related signalling pathways. A substantial share of the human data originates from a limited number of research groups, and independent replication in other countries remains sparse. Regulatory status reflects that distribution: the peptide is registered as a medicine in Russia and appears in some neighbouring markets, while elsewhere it is handled as a research chemical without approved therapeutic labelling. Questions about dose-response relationships, long-term effects, and comparability across studies are still open.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white powder | Lyophilized solid from research suppliers |
| Solubility | Freely soluble in water | Also dissolves in aqueous buffers; solutions are used fresh |
| Typical storage temperature | -20 °C for lyophilized powder | Short-term transport at 2-8 °C is common |
| Common analytical method | Reverse-phase HPLC | Paired with mass spectrometry for identity confirmation |
| Common synonyms | ACTH(4-10) analogue; MEHFPGP | N-terminal methionine retained in the chain |
Published studies are dominated by animal models of stroke, ischemia, and cognitive impairment, with a smaller number of human trials conducted in Russia. Many of the human reports are small, single-center, and published in Russian-language journals, which limits independent scrutiny. Outcome measures vary between studies and often rely on clinician-rated scales rather than objective biomarkers. Systematic reviews have noted the methodological weaknesses and called for larger, preregistered trials before firm conclusions can be drawn.
Claims about enhanced focus, memory, or mood in healthy people rest mostly on anecdotal reports and community discussion rather than on controlled data. It remains unclear whether any cognitive benefit observed in patients recovering from brain injury would extend to uninjured users. Dose-response relationships, long-term safety, and interactions with other drugs are not well characterized in the peer-reviewed literature. Questions about optimal route of administration and treatment duration likewise remain open.
Semax binds to melanocortin receptors and is thought to influence neuronal survival and plasticity rather than to act through the adrenal axis. Laboratory work has shown increased expression of brain-derived neurotrophic factor and nerve growth factor in treated tissue. Changes in c-Fos, a marker of neuronal activation, have also been reported. Because the peptide is rapidly degraded by peptidases, its effects are generally attributed to downstream signaling cascades rather than to sustained receptor occupancy.
Identity and purity of Semax are established mainly by reversed-phase high-performance liquid chromatography coupled with mass spectrometry. The chromatographic trace gives a purity estimate as a percentage of total peak area, while electrospray or matrix-assisted laser desorption ionization confirms the molecular mass against the calculated value. Amino acid analysis and sequence-specific fragmentation provide further confirmation when a supplier's chain of custody is unclear. Vendors frequently quote a purity figure without stating the detection wavelength or the integration method, which limits how far one number can be compared with another.
Stability depends heavily on physical state. Lyophilized powder held dry, cold and dark retains its content over long periods, whereas dissolved peptide begins to change within days at room temperature. The most cited degradation route is oxidation of the methionine residue, which converts the peptide to a sulfoxide form that elutes differently on chromatography. Hydrolysis of amide bonds and adsorption onto container walls contribute smaller losses. Buffers that exclude oxygen from the headspace slow the oxidation pathway, but no single condition prevents all change indefinitely.
Practical handling follows from those properties. Bulk material is best divided into single-use portions soon after receipt, because each thaw exposes the whole container to moisture and temperature cycling. Vials should be allowed to reach room temperature before opening to prevent condensation on the powder. Low-binding plasticware reduces loss of dilute solutions, and sterile filtration is used when a preparation must remain free of microbial growth. Records of batch number, reconstitution date and storage history are what allow a later analytical result to be interpreted meaningfully.
Published research covers ischemic stroke, traumatic brain injury, cognitive impairment, optic nerve conditions and attention-related measures. Much of the human evidence comes from small trials conducted in one country, which limits how far the results generalize. Animal models supply the larger share of the data, and effects seen in rodents do not transfer automatically to people. Reviews have noted that methodological reporting is often incomplete, making it difficult to pool results or compare treatment schedules across studies.
Pharmacokinetic accounts emphasize rapid breakdown. After intravenous dosing the intact peptide disappears from blood within minutes, and nasal delivery produces low but measurable concentrations. Metabolites rather than the parent molecule may account for part of the observed activity, although the relative contribution is unresolved. Dosing in the literature varies widely and no optimal schedule has been agreed. These gaps are regularly cited as a reason the findings have not produced broad clinical adoption beyond the original research setting.
Proposed mechanisms center on neurotrophic signaling rather than on classical melanocortin receptor activation. Rodent experiments have reported shifts in the expression of brain-derived neurotrophic factor and nerve growth factor after administration, together with changes in the associated receptor systems. Several authors argue that the peptide acts largely through its degradation products and their interaction with peptidergic pathways, but this remains a hypothesis rather than a settled finding. No single molecular target has been identified in a way that the field broadly accepts.
=== Final tour and death in New York === Thomas left Laugharne on 9 October 1953 on the first leg of his fourth trip to America. He called on his mother, Florence, to say goodbye: "He always felt that he had to get out from this country because of his chest being so bad." Thomas had suffered from chest problems for most of his life, though they began in earnest soon after he moved in May 1949 to the Boat House at Laugharne—the "bronchial heronry", as he called it. Within weeks of moving in, he visited a local doctor, who prescribed medicine for both his chest and throat. While waiting in London before his flight, Thomas stayed with the comedian Harry Locke and worked on Under Milk Wood. Locke noted that Thomas was having trouble with his chest, "terrible" coughing fits that made him go purple in the face. He was also using an inhaler to help his breathing. There were reports, too, that Thomas was also having blackouts. His visit to the BBC producer Philip Burton, a few days before he left for New York, was interrupted by a blackout. On his last night in London, he had another in the company of his fellow poet Louis MacNeice. Thomas arrived in New York on 20 October 1953 to undertake further performances of Under Milk Wood, organised by John Brinnin, his American agent and Director of the Poetry Centre. Brinnin did not travel to New York but remained in Boston to write. He handed responsibility to his assistant, Liz Reitell. She met Thomas at Idlewild Airport and was shocked at his appearance.
=== Built under license === Focke-Wulf C.19 – license-built (autogyro)– licence-built version of the Cierva C.19, with Siemens Sh 14 engine. (one prototype, converted from Cierva C.19 Mk.IV) Focke-Wulf C.30 Heuschrecke (Grasshopper) – licence-built version of the Cierva C.30, with Siemens Sh 14 engine. Focke-Wulf FWP.149D – license-built Piaggio P.149
==== Granuloma ==== Drug-induced hepatic granulomas are usually associated with granulomas in other tissues and patients typically have features of systemic vasculitis and hypersensitivity. More than 50 drugs have been implicated.
Sources: en.wikipedia.org
Plastination is a technique or process used in anatomy to preserve bodies or body parts, first developed by Gunther von Hagens in 1977. The water and fat are replaced by certain plastics, yielding specimens that can be touched, do not smell or decay, and even retain most properties of the original sample.
Irregular periods: periods may stop completely or may be less frequent. When they do happen, periods can be very heavy. There may be menstrual bleeding without ovulation, too; around 40% of women with PMOS who have a regular cycle have periods without ovulation. Infertility: PMOS is one of the leading causes of infertility in women. A "male" pattern of hair growth, including hair on the chin, upper lip, chest, upper thighs, and on the belly. This growth pattern, called hirsutism, is present in about 60% of women with PMOS. Acne: Acne is typically severe, persists beyond adolescence, or continues despite standard treatment. Pattern hair loss (androgenic alopecia), at the top of the scalp Skin issues, such as oily skin or a condition where dark, thick, and "velvety" patches can form (acanthosis nigricans) The ovaries might be larger than normal, with many small fluid-filled sacs that surround eggs ("follicles"). Testosterone levels are usually elevated: one meta-analysis showed testosterone levels to be 1.5 times higher in women with PMOS compared to women without PMOS.
== Pathophysiology == Copper functions as a prosthetic group, permitting electron transfers in key enzymatic pathways like the electron transport chain. Copper is integrated in the enzymes cytochrome c oxidase, which is involved in cellular respiration and oxidative phosphorylation, Cu/Zn dismutase, which is involved in antioxidant defense, and many more listed in the table below.
Anti-centromere antibodies are associated with limited cutaneous systemic sclerosis, also known as CREST syndrome, primary biliary cirrhosis and proximal scleroderma. There are six known antigens, which are all associated with the centromere; CENP-A to CENP-F. CENP-A is a 17kDa histone H3-like protein. CENP-B is an 80kDa DNA binding protein involved in the folding of heterochromatin. CENP-C is a 140kDa protein involved in kinetochore assembly. CENP-D is a 50kDa protein of unknown function, but may be homologous to another protein involved in chromatin condensation, RCC1. CENP-E is a 312kDa protein from the kinesin motor protein family. CENP-F is a 367kDa protein from the nuclear matrix that associates with the kinetochore in late G2 phase during mitosis. CENP-A, B and C antibodies are most commonly found (16–42% of systemic sclerosis) and are associated with Raynaud's phenomenon, telangiectasias, lung involvement and early onset in systemic sclerosis. Anti-centromere antibodies are found in approximately 60% of patients with limited systemic scleroderma and in 15% of those with the diffuse form of scleroderma. The specificity of this test is >98%. Thus, a positive anti-centromere antibody finding is strongly suggestive of limited systemic scleroderma. Anti-centromere antibodies present early in the course of disease and are notably predictive of limited cutaneous involvement and a decreased likelihood of aggressive internal organ involvement, such as fibrosis in the lungs.
Sources: en.wikipedia.org
The cattle boats were examined, but the dates of the murders did not coincide with a single boat's movements, and the transfer of a crewman between boats was also ruled out. At the end of October, Robert Anderson asked police surgeon Thomas Bond to give his opinion on the extent of the murderer's surgical skill and knowledge. The opinion offered by Bond on the character of the "Whitechapel murderer" is the earliest surviving offender profile. Bond's assessment was based on his own examination of the most extensively mutilated victim and the post mortem notes from the four previous canonical murders. In his opinion the killer must have been a man of solitary habits, subject to "periodical attacks of homicidal and erotic mania", with the character of the mutilations possibly indicating "satyriasis". Bond also stated that "the homicidal impulse may have developed from a revengeful or brooding condition of the mind, or that religious mania may have been the original disease but I do not think either hypothesis is likely".
Valve was founded in 1996 by the former Microsoft employees Gabe Newell and Mike Harrington. Newell had spent the prior 13 years at Microsoft developing Windows, including the Windows 95 port of Doom from id Software. Newell had become frustrated with game developers' approach of creating bespoke interfaces for graphics acceleration, and had also seen id Software outperforming Windows in sales of Doom with an alternative distribution model. Newell and Harrington founded Valve, L.L.C. in Kirkland, Washington, about five miles from the Microsoft campus in Redmond, on August 24, 1996, Newell's wedding day. In a break from industry style of the time, Newell did not want a company name that suggested "testosterone-gorged muscles and the 'extreme' of anything". Alternative names considered by Newell and Harrington include Hollow Box, Fruitfly Ensemble and Rhino Scar. Valve's first game was Half-Life, a first-person shooter (FPS) with elements of horror. The development was aided by access to the Quake engine by id Software; Valve modified this engine into its GoldSrc engine. After struggling to find a publisher, Valve eventually signed with Sierra On-Line. Half-Life was released in November 1998 and was a critical and commercial success. With its realism, scripted sequences and seamless narrative, it had a lasting influence; according to IGN in 2014, the history of the FPS genre "breaks down pretty cleanly into pre-Half-Life and post-Half-Life eras".
The pharmacology of estradiol, an estrogen medication and naturally occurring steroid hormone, concerns its pharmacodynamics, pharmacokinetics, and various routes of administration. Estradiol is a naturally occurring and bioidentical estrogen, or an agonist of the estrogen receptor, the biological target of estrogens like endogenous estradiol. Due to its estrogenic activity, estradiol has antigonadotropic effects and can inhibit fertility and suppress sex hormone production in both women and men. Estradiol differs from non-bioidentical estrogens like conjugated estrogens and ethinylestradiol in various ways, with implications for tolerability and safety. Estradiol can be taken by mouth, held under the tongue, as a gel or patch that is applied to the skin, in through the vagina, by injection into muscle or fat, or through the use of an implant that is placed into fat, among other routes.
Sources: en.wikipedia.org
It consists mainly of animal experiments and small clinical reports, with much of the clinical material published in Russian-language journals. Large independent trials are scarce. Separating reliable effects from chance findings is consequently difficult.
A fraction of an intranasal dose is thought to reach the central nervous system, and this route is favoured partly for that reason. The proportion is not well characterized. Direct measurement in humans remains difficult with current methods.
Raised BDNF and NGF expression has been reported across several animal studies, which makes the signal fairly consistent. Whether the same change occurs in humans at usable doses is not established. It is best treated as a working hypothesis rather than a confirmed clinical mechanism.
Reversed-phase HPLC gives the main purity figure, most often with UV detection near 214 nanometres. Mass spectrometry then confirms the molecular mass. Together the two methods distinguish a correct sequence from a closely related impurity.